JPWO2013011927A1 - Molten glass conveying equipment element, molten glass conveying equipment element manufacturing method, and glass manufacturing apparatus - Google Patents

Abstract

The present invention relates to a molten glass conduit structure including at least one conduit made of platinum or a platinum alloy, a first ceramic structure disposed around the conduit, and a periphery of the first ceramic structure. A method for manufacturing a molten glass conveying equipment element having a second ceramic structure positioned, wherein 75 wt.% Of zirconium oxide is contained in the gap between the conduit and the second ceramic structure in a mass% of the total composition. %, And the proportion of cubic zirconia in the zirconium oxide is 80 wt% or more, and at least one selected from the group consisting of yttrium oxide and cerium oxide as a stabilizer is 6 in total content. First stabilized zirconia particles containing ˜25 wt% and having a median diameter D50 of 0.2 to 5 μm and media The second stabilized zirconia particles having a diameter D50 of 0.2 to 2 mm are mixed with a mass ratio of the first stabilized zirconia particles to the second stabilized zirconia particles (mass of first stabilized zirconia particles / The first ceramic structure is formed by filling a slurry body blended so that the mass of the stabilized zirconia particles of 2 is 0.3 to 0.6 and sintering at a temperature of 1200 to 1700 ° C. It is related with the manufacturing method of the molten glass conveyance equipment element.

Description

  The present invention relates to a molten glass conveying equipment element that can be suitably used in a glass manufacturing apparatus such as a vacuum degassing apparatus, a method for producing the molten glass conveying equipment element, and a glass manufacturing apparatus that includes the molten glass conveying equipment element.

In a glass manufacturing apparatus such as a vacuum degassing apparatus, a constituent material of a molten glass conduit is required to have excellent heat resistance and corrosion resistance to molten glass. As a material that satisfies this requirement, platinum or a platinum alloy is used (see Patent Document 1). A heat insulating brick is disposed around a conduit made of platinum or a platinum alloy molten glass so as to surround the conduit.
Since the thermal expansion coefficient is different between platinum or platinum alloy constituting the conduit and the insulating bricks arranged around the conduit, there is a difference in the amount of thermal expansion during heating and the amount of contraction during cooling. It becomes a problem.
In order to absorb the difference in the amount of thermal expansion during heating or the amount of shrinkage during cooling, castable cement is used between the two so that the two can move slightly when the temperature changes. Is filled with an irregular ceramic material.

Depending on the arrangement of the molten glass conduits, the inventors of the present application may not be able to absorb the difference in thermal expansion during heating or the difference in shrinkage during cooling when filled with an irregular ceramic material. I found. For example, at the joint between a vertical tube and a horizontal tube, the difference in thermal expansion during heating or the difference in shrinkage during cooling cannot be absorbed by an amorphous ceramic material, and cracks are not generated at the joint. May occur. When a crack occurs at the joint, there is a problem that the insulating brick disposed around is eroded by the molten glass leaking from the crack. As a result, there are problems such as a decrease in productivity due to restoration work and a shortened equipment life.
In order to solve such a problem, the inventors of the present application provided a molten glass conveying equipment element and a glass manufacturing apparatus described in Patent Document 2.
In the molten glass conveyance equipment element described in Patent Document 2, a ceramic structure having a linear thermal expansion coefficient substantially equal to that of platinum or platinum alloy constituting the conduit is disposed around a conduit of platinum or a platinum alloy molten glass. By doing so, the difference in the amount of thermal expansion during heating or the amount of shrinkage during cooling becomes extremely small. For this reason, it is prevented that a crack is generated at the joint between the vertical tube and the horizontal tube due to thermal expansion during heating or contraction during cooling.

Japanese Unexamined Patent Publication No. 2002-87826 International Publication No. 2010/0667669

In the molten glass conveyance equipment element described in Patent Document 2, by providing a gap between a platinum or platinum alloy conduit and a ceramic structure, thermal expansion during heating or cooling between the two is provided. Although it is said that it is possible to absorb the shift in the timing of contraction and to prevent the occurrence of cracks at the joint, the presence of such a gap may cause deformation and breakage of the conduit.
In the molten glass conveying equipment element described in Patent Document 2, it is considered that a platinum or platinum alloy conduit has sufficient strength in use. The strength of the conduit may be reduced due to deterioration or the like. Moreover, the use form of a molten-glass conveyance equipment element changes, for example, the expansion pressure added from a molten glass may increase by stirring the molten glass which passes the inside of a conduit | pipe with a stirrer. As a result, the strength of the conduit becomes insufficient with respect to the expansion pressure applied from the molten glass, and the conduit may be deformed and broken.

  In order to prevent the deformation of the conduit, the ceramic structure may be disposed without providing a gap around the conduit. However, depending on the arrangement of the conduit and the shape of the conduit, the gap may not be provided around the conduit. It may be difficult to arrange the ceramic structure. For example, it is difficult to dispose a ceramic structure without providing a gap around a conduit at a joint between a vertical pipe and a horizontal pipe. In addition, Japanese National Publication No. 2004-070251 discloses a hollow tube made of platinum or a platinum alloy provided with at least one convex portion continuous 360 degrees in the circumferential direction in order to absorb expansion and contraction due to heat. ing. Further, Japanese Patent Application Laid-Open No. 2006-315894 discloses that 360 degree continuous in the circumferential direction in order to prevent the conduit from being damaged by applying thermal stress or external stress during long-term use. A hollow tube made of platinum or a platinum alloy in which convex portions and concave portions are alternately provided along the axial direction is disclosed, but a gap is provided around a conduit provided with such convex portions and concave portions. It is difficult to dispose a ceramic structure without using it.

  In order to solve the above-described problems of the prior art, the present invention achieves prevention of cracking of the conduit by thermal expansion during heating or contraction during cooling, and prevention of deformation of the conduit due to expansion pressure applied from the molten glass. In addition, even if the molten glass leaks for some reason, the molten glass conveying equipment element having the ceramic structure that is not easily eroded, the manufacturing method of the molten glass conveying equipment element, and the molten glass conveying equipment element It aims at providing the glass manufacturing apparatus containing this.

To achieve the above object, the present invention provides a molten glass conduit structure including at least one conduit made of platinum or a platinum alloy, a first ceramic structure disposed around the conduit, and the first A method for producing a molten glass conveying equipment element having a second ceramic structure located around a ceramic structure of one,
In the gap between the conduit and the second ceramic structure, zirconium oxide is contained in an amount of 75 wt% or more by mass% based on the total composition, and the proportion of cubic zirconia in the zirconium oxide is 80 wt% or more. A first stabilized zirconia having a median diameter D50 of 0.2 to 5 μm, containing 6 to 25 wt% of the total content of at least one selected from the group consisting of yttrium oxide and cerium oxide as a stabilizer Particles, and a second stabilized zirconia particle having a median diameter D50 of 0.2 to 2 mm, a mass ratio of the first stabilized zirconia particle to the second stabilized zirconia particle (first stabilized zirconia) The slurry body was mixed so that the mass of the particles / the mass of the second stabilized zirconia particles) was 0.3 to 0.6. Wherein by causing sintered at a temperature of 1200 to 1700 ° C. first ceramic structure is formed, to provide a method of manufacturing a molten glass conveying equipment element.

Further, the present invention is a molten glass transport equipment element manufactured by the method for manufacturing a molten glass transport equipment element of the present invention, wherein the average open porosity of the first ceramic structure is 25-60%, The linear thermal expansion coefficient of the first ceramic structure at 20 to 1000 ° C. is 8 × 10 ^{−6 to} 12 × 10 ⁻⁶ / ° C., and the gap between the conduit and the first ceramic structure is 0. A molten glass transport equipment element is provided that is less than 5 mm.

  Moreover, this invention provides the glass manufacturing apparatus containing the molten glass conveyance equipment element of this invention.

  According to the method for manufacturing a molten glass conveying equipment element of the present invention, the first ceramics having a predetermined average open porosity with a linear thermal expansion coefficient substantially the same as that of platinum or a platinum alloy constituting the molten glass conduit. The structure can be formed without any gap around the conduit of molten glass made of platinum or platinum alloy without being affected by the arrangement or shape of the conduit.

In the molten glass conveying equipment element of the present invention, the linear thermal expansion coefficients of the molten glass conduit made of platinum or a platinum alloy and the ceramic structure disposed around the conduit are substantially the same. The difference in thermal expansion amount or shrinkage amount during cooling is extremely small. For this reason, cracks occur in the conduit due to thermal expansion during heating or contraction during cooling, for example, at the junction between a conduit having a central axis in the vertical direction and a conduit having a central axis in the horizontal direction. Occurrence is prevented. Furthermore, even if the molten glass leaks for some reason, the ceramic structure in the present invention is hardly eroded.
Further, in the molten glass conveying equipment element of the present invention, the first ceramic structure having sufficient compressive strength is formed without providing a gap around the molten glass conduit in the temperature range when the molten glass flows. Therefore, the conduit is prevented from being deformed by the expansion pressure applied from the molten glass passing through the inside.
In the glass manufacturing apparatus of the present invention including such a molten glass conveying equipment element, cracks are prevented from occurring in the conduit due to thermal expansion during heating or contraction during cooling, and melting that passes through the inside. Excellent reliability due to the fact that the duct is prevented from being deformed by the expansion pressure applied from the glass and that the ceramic structure is less likely to erode even if the molten glass leaks for some reason. Thus, glass can be produced stably over a long period of time.

FIG. 1 is a cross-sectional view showing one configuration example of the molten glass conveying equipment element of the present invention. FIG. 2 is a cross-sectional view showing another configuration example of the molten glass conveyance facility element of the present invention. FIG. 3 is a graph showing the relationship between the load time and the amount of compressive strain. FIG. 4 shows the state of the conduit before and after the compressive strain test.

The present invention will be described below with reference to the drawings.
FIG. 1 is a cross-sectional view showing one configuration example of the molten glass conveying equipment element of the present invention.
In the molten glass conveying equipment element shown in FIG. 1, the molten glass conduit structure 1 has a central axis in the horizontal direction with respect to a conduit having a central axis in the vertical direction (hereinafter referred to as “vertical tube”) 1a. Two conduits (hereinafter referred to as “horizontal pipes”) 1b and 1b communicate with each other.

  In FIG. 1, a first ceramic structure 2 is arranged around the conduits (vertical tube 1 a and horizontal tube 1 b) constituting the molten glass conduit structure 1, and the first ceramic structure 2. The second ceramic structure 3 is located around the.

The molten glass conveyance equipment element in the present invention is not limited to the illustrated embodiment as long as it has at least one conduit.
FIG. 2 is a cross-sectional view showing another configuration example of the molten glass conveyance facility element of the present invention.
In the molten glass conveying equipment element shown in FIG. 2, the molten glass conduit structure 1 has only one conduit 1c. The conduit 1c is provided with convex portions and concave portions that continue 360 degrees in the circumferential direction alternately along the axial direction, and has an accordion-shaped outer shape.
Also in FIG. 2, the first ceramic structure 2 is disposed around the conduit 1 c constituting the molten glass conduit structure 1, and the second ceramic structure 2 is surrounded by the second ceramic structure 2. The ceramic structure 3 is located.

In the case of a structure in which a vertical tube and a horizontal tube are communicated as shown in FIG. 1, the conduits (vertical tube 1a, horizontal tube 1b) constituting the molten glass conduit structure 1 and ceramics arranged around the conduits If the difference in thermal expansion coefficient between the structure and the structure is large, the difference in thermal expansion during heating or the difference in shrinkage during cooling cannot be absorbed by the elongation of the tube material, and the vertical pipe 1a and the horizontal Since there is a possibility that cracks may occur at the joint with the tube 1b, the heat of the conduit constituting the conduit structure 1 for molten glass and the first ceramic structure 2 disposed around the conduit 1 It is preferable to apply the present invention in which the difference in the expansion coefficient is small and the occurrence of cracks in the conduit constituting the molten glass conduit structure 1 can be suppressed by thermal expansion during heating or contraction during cooling. It is.
Further, in the vicinity of the joint portion between the vertical pipe 1a and the horizontal pipe 1b, between the conduit (vertical pipe 1a, horizontal pipe 1b) and a ceramic structure such as a refractory brick disposed around the conduit. Since there is a risk that a gap is easily formed in the glass and the expansion pressure applied from the molten glass deforms and breaks the conduit, the conduit (vertical tube 1a, horizontal tube 1b) constituting the molten glass conduit structure 1 and the It is preferable to apply the present invention in which the gap between the first ceramic structure 2 and the surrounding surroundings is extremely small, and the deformation of the conduit due to the expansion pressure applied from the molten glass can be suppressed.
The structure in which the vertical pipe and the horizontal pipe communicate with each other as shown in FIG. 1 is not limited to the illustrated embodiment, and one horizontal pipe may communicate with one vertical pipe. Good. Further, one horizontal pipe communicates with one vertical pipe at one end side, and the horizontal pipe communicates with another vertical pipe at the other end side. Alternatively, one or more vertical pipes or horizontal pipes, or both may communicate with such a structure.

  Further, the vertical pipe in the present invention does not necessarily require that the central axis is in the vertical direction in a strict sense, and the central axis may be inclined with respect to the vertical direction. The same applies to the horizontal pipe, and the central axis is not necessarily required to be in the horizontal direction in a strict sense, and the central axis may be inclined to some extent with respect to the horizontal direction. In short, the vertical pipe and the horizontal pipe in the present invention are intended to have a relative relationship between them, and when one of the pipes is a vertical pipe, the pipe intersecting with the vertical pipe is the horizontal pipe. It is.

Moreover, when the conduit | pipe which comprises the conduit | pipe structure for molten glass has an unevenness | corrugation like the conduit | pipe 1c shown in FIG. 2, between ceramic structures, such as a refractory brick arrange | positioned around this conduit | pipe, Since the gap is likely to occur and the expansion pressure applied from the molten glass may deform and damage the conduit, the conduit 1c constituting the molten glass conduit structure 1 and the first around the conduit 1c are arranged. It is preferable to apply the present invention in which the gap between the ceramic structure 2 and the ceramic structure 2 is extremely small and the deformation of the conduit due to the expansion pressure applied from the molten glass can be suppressed.
In the case where only one conduit as shown in FIG. 2 is provided, as shown in the drawing, convex portions and concave portions continuous 360 degrees in the circumferential direction are alternately provided along the axial direction. It is not limited, You may have only one among a convex part or a recessed part, Furthermore, the normal straight pipe which does not have a convex part and a recessed part may be sufficient.

Moreover, the stirrer for stirring molten glass may be provided in the inside of the conduit | pipe which comprises the conduit | pipe structure for molten glass.
When a stirrer for stirring molten glass is provided inside the conduit constituting the conduit structure for molten glass, the conduit may be deformed and damaged by the expansion pressure applied from the molten glass during stirring by the stirrer. Therefore, the gap between the conduit constituting the conduit structure for molten glass and the first ceramic structure disposed around the conduit is extremely small, and the deformation of the conduit due to the expansion pressure applied from the molten glass can be suppressed. It is preferable to apply the invention.

In the present invention, the conduits constituting the molten glass conduit structure 1 (vertical tube 1a, horizontal tube 1b, and conduit 1c in FIG. 2) are used as molten glass conduits. The constituent material is required to have excellent heat resistance and corrosion resistance to molten glass. For this reason, the conduits constituting the molten glass conduit structure 1 (vertical tube 1a, horizontal tube 1b, and conduit 1c in FIG. 2) are platinum, platinum-gold alloy, platinum-rhodium alloy, platinum- It consists of a platinum alloy such as an iridium alloy.
Platinum or a platinum alloy constituting the conduits constituting the molten glass conduit structure 1 (vertical pipe 1a, horizontal pipe 1b in FIG. 1 and conduit 1c in FIG. 2) is composed of Al ₂ O ₃ , platinum or platinum alloy, It is preferably made of reinforced platinum in which metal oxide particles such as ZrO ₂ and Y ₂ O ₃ are dispersed. In reinforced platinum, metal oxide particles dispersed in platinum or a platinum alloy have an effect of hindering dislocations and growth of crystal grains, thereby increasing mechanical strength. On the other hand, however, the ductility of the material is lower than that of normal platinum or a platinum alloy, so that the conduit constituting the molten glass conduit structure 1 and ceramics such as a heat insulating brick disposed around the conduit are included. The difference in thermal expansion during heating with the structure or the difference in shrinkage during cooling cannot be absorbed by the elongation of the tube material, and there is a risk that the conduit will crack. For this reason, it is a suitable material to apply this invention which can suppress generation | occurrence | production of the crack in the conduit | pipe which comprises the conduit structure 1 for molten glass by the thermal expansion at the time of heating, or the shrinkage | contraction at the time of cooling. Can do.

In the present invention, the first ceramic structure 2 contains 75 wt% or more of zirconium oxide in mass% with respect to the entire composition, and the proportion of cubic zirconia in the zirconium oxide is 80 wt% or more. In other words, the first ceramic structure 2 is mainly composed of cubic zirconia which is fully stabilized zirconia.
By using cubic zirconia as a main component, the amount of thermal expansion during heating or the amount of shrinkage during cooling is a conduit constituting the conduit structure 1 for molten glass and the first ceramic disposed around the conduit. The structure 2 is almost the same. As a result, the difference between the amount of thermal expansion during heating or the amount of shrinkage during cooling becomes extremely small, and cracks occur in the conduits constituting the molten glass conduit structure 1 due to thermal expansion during heating or shrinkage during cooling. For example, cracks are prevented from occurring at the joint between the vertical tube 1a and the horizontal tube 1b in FIG.
This is because cubic zirconia, which is a fully stabilized zirconia, has a linear thermal expansion coefficient very close to that of platinum or a platinum alloy constituting the conduit at 20 to 1000 ° C. as shown below.
Platinum, platinum alloy: 9.5 × 10 ⁻⁶ / ° C. to 11 × 10 ⁻⁶ / ° C.
Cubic ^{Zirconia: 8.5 × 10 -6 /℃~10.5×10 -6 /} ℃
Zirconium oxide such as cubic zirconia is excellent in heat resistance, corrosion resistance of molten glass, corrosion resistance against corrosive gas, and the like. Therefore, the conduits constituting the conduit structure 1 for molten glass (vertical tube in FIG. 1). It is suitable as the first ceramic structure 2 disposed around 1a, the horizontal pipe 1b, and the conduit 1c) of FIG.

In order to achieve the above effects, the linear thermal expansion coefficient at 20 to 1000 ° C. of the ceramic structure is 8 × 10 ^{−6 to} 12 × 10 ⁻⁶ / ° C., and 9 × 10 ^{−6 to} 11 × 10 ^−6. / ° C. is preferable, and 9.5 × 10 ^{−6 to} 10.5 × 10 ⁻⁶ / ° C. is more preferable.
However, since the linear thermal expansion coefficient of platinum or a platinum alloy is slightly different depending on the composition, the conduits constituting the molten glass conduit structure 1 (vertical tube 1a, horizontal tube 1b in FIG. 1, and conduit 1c in FIG. 2) are used. It is preferable to select the linear thermal expansion coefficient of the first ceramic structure 2 according to the linear thermal expansion coefficient of platinum or platinum alloy to be used. Specifically, the linear thermal expansion coefficient at 20 to 1000 ° C. of the first ceramic structure 2 is a conduit constituting the molten glass conduit structure 1 (vertical tube 1a, horizontal tube 1b in FIG. 1, and FIG. 2 is preferably within ± 15%, more preferably within ± 10%, more preferably within ± 5% of the linear thermal expansion coefficient at 20 to 1000 ° C. of platinum or platinum alloy used for the conduit 1c). Is more preferable.

  In order to achieve the above linear thermal expansion coefficient, zirconium oxide contained in the first ceramic structure 2 is 75 wt% or more, and the proportion of cubic zirconia in the zirconium oxide needs to be 80 wt% or more. The proportion of cubic zirconia in the zirconium oxide contained in the first ceramic structure 2 is preferably 85 wt% or more, and more preferably 90 wt% or more.

In the present invention, the first ceramic structure 2 has an average open porosity of 25 to 60%. The first ceramic structure 2 having the above composition is excellent in corrosion resistance to the molten glass, but if the average open porosity is more than 60%, the corrosion resistance to the molten glass is lowered. On the other hand, if the average open porosity is less than 25%, the thermal shock resistance of the first ceramic structure 2 is lowered. Further, since the heat capacity is increased, the conduits constituting the molten glass conduit structure 1 (vertical tube 1a, horizontal tube 1b, and conduit 1c in FIG. 2), the first ceramic structure 2, In the meantime, the thermal expansion at the time of heating or the timing of the contraction at the time of cooling tends to be shifted, and there is a possibility that cracks may occur in the conduits constituting the molten glass conduit structure 1. In addition, the time required for heating or cooling becomes longer.
The first ceramic structure 2 preferably has an average open porosity of 30 to 50%, and more preferably 35 to 45%.
The average open porosity of the 1st ceramic structure 2 can be calculated | required by the measurement by Archimedes method or mercury porosimetry.
The first ceramic structure 2 may have different open porosity depending on the part. For example, the open porosity of the portion facing the conduits (vertical tube 1a, horizontal tube 1b in FIG. 1 and conduit 1c in FIG. 2) constituting the molten glass conduit structure 1 is made lower than the other portions. Thus, the corrosion resistance against molten glass can be enhanced.

1 and 2, between the conduits (vertical tube 1a, horizontal tube 1b in FIG. 1 and conduit 1c in FIG. 2) constituting the molten glass conduit structure 1, and the first ceramic structure 2. There are no gaps.
As described above, between the conduits constituting the molten glass conduit structure 1 (vertical tube 1a, horizontal tube 1b, and conduit 1c in FIG. 2) and the first ceramic structure 2 are provided. If there is a gap, the expansion pressure applied from the molten glass may deform and damage the conduit.
If there is no gap between the conduits constituting the molten glass conduit structure 1 (vertical tube 1a, horizontal tube 1b, and conduit 1c in FIG. 2) and the first ceramic structure 2, The deformation of the conduit due to the expansion pressure applied from the molten glass can be suppressed.
However, in the present invention, the gap between the conduits constituting the molten glass conduit structure 1 (vertical tube 1a, horizontal tube 1b, and conduit 1c in FIG. 2) and the first ceramic structure 2 is the same. Should be extremely small, specifically, less than 0.5 mm.
The gap between the conduits constituting the molten glass conduit structure 1 (vertical tube 1a, horizontal tube 1b, and conduit 1c in FIG. 2) and the first ceramic structure 2 is 0.4 mm or less. Is preferably 0.2 mm or less, and more preferably no gap is present.

  The first ceramic structure 2 has a sufficient compressive strength in the temperature range when the molten glass flows in order to suppress deformation of the conduit constituting the molten glass conduit structure 1 by the expansion pressure applied from the molten glass. It is required to do. Specifically, the first ceramic structure 2 preferably has a compressive strength at 1400 ° C. of 5 MPa or more, more preferably 8 MPa or more, and further preferably 10 MPa or more. Here, the compressive strength at 1400 ° C. is because the temperature is normally experienced by the first ceramic structure 2 when the molten glass is distributed.

In the present invention, the thickness d of the first ceramic structure 2 is preferably 15 mm or more and 50 mm or less. When the thickness d of the first ceramic structure 2 is less than 15 mm, the second ceramic structure 3 hinders the amount of thermal expansion during heating or the amount of contraction during cooling of the first ceramic structure 2. Therefore, between the conduits constituting the molten glass conduit structure 1 (vertical tube 1a, horizontal tube 1b, and conduit 1c in FIG. 2) and the first ceramic structure 2 during heating. The difference in the amount of thermal expansion or the amount of shrinkage during cooling increases, and there is a risk that cracks will occur in the conduit constituting the conduit structure 1 for molten glass.
If the thickness d of the first ceramic structure 2 is less than 15 mm, the slurry is formed in the gap between the conduit constituting the molten glass conduit structure 1 and the second ceramic structure 3 in the procedure described later. When the first ceramic structure 2 is formed by filling the body and sintering the slurry body, the workability may be inferior.
Since cubic zirconia is an expensive material, it is preferable from the viewpoint of cost to keep the thickness of the first ceramic structure 2 to the minimum necessary. From this viewpoint, the thickness d of the first ceramic structure 2 is preferably 50 mm or less.
If the thickness d of the first ceramic structure 2 is larger than 50 mm, a temperature difference may occur in the thickness direction of the first ceramic structure 2 when the molten glass is distributed.
The thickness d of the first ceramic structure 2 is more preferably 20 to 40 mm, and further preferably 25 to 35 mm.
In addition, when the conduit | pipe which comprises the conduit structure 1 for molten glass has an unevenness | corrugation like the conduit | pipe 1c of FIG. 2, thickness is in all the site | parts of the 1st ceramic structure 2 facing the unevenness | corrugation of the conduit | pipe 1c. The above range should be satisfied.

As described above, since cubic zirconia is an expensive material, the thickness of the first ceramic structure 2 is such that the conduit constituting the molten glass conduit structure 1, the second ceramic structure 3, In order to form the first ceramic structure 2 by filling the gap between the slurry body and sintering the slurry body, the second ceramic structure 3 is positioned around the first ceramic structure 2. Will do.
As the second ceramic structure 3, a heat insulating brick mainly composed of at least one selected from the group consisting of alumina, magnesia, zircon and silica can be used.
Specific examples of the heat insulating brick used as the second ceramic structure 3 include silica / alumina heat insulating brick, zirconia heat insulating brick, and magnesia heat insulating brick. Examples of commercially available products include SP-15 (manufactured by Hinomaru Ceramic Co., Ltd.), LBK3000 (manufactured by Isolite Kogyo Co., Ltd.), and the like.

Next, the manufacturing method of the molten glass conveyance equipment element of this invention is demonstrated.
In the present invention, the gap between the conduits constituting the molten glass conduit structure 1 (vertical tube 1a, horizontal tube 1b, and conduit 1c in FIG. 2) and the first ceramic structure 2 is set to 0. Although it is required to be less than 5 mm, if the insulating brick mainly composed of cubic zirconia, which is a completely stabilized zirconia, is arranged around the conduit constituting the conduit structure 1 for molten glass, the above gap Cannot be achieved.
For this reason, in the present invention, stabilized zirconia satisfying the composition of the first ceramic structure 2 described above (that is, zirconium oxide is 75 wt% or more and the proportion of cubic zirconia in the zirconium oxide is 80 wt% or more). A slurry body containing particles is formed by a conduit (a vertical tube 1a, a horizontal tube 1b, and a conduit 1c in FIG. 2) constituting the molten glass conduit structure 1 and a second ceramic structure 3. The first ceramic structure 2 is formed by filling the gap and sintering the slurry.

  Here, the gap between the first ceramic structure 2 after formation and the conduits (vertical tube 1a, horizontal tube 1b in FIG. 1, and conduit 1c in FIG. 2) constituting the molten glass conduit structure 1. Is included in the slurry body to be used so that the first ceramic structure 2 after the formation has a sufficient compressive strength in the temperature range when the molten glass flows. It is necessary to select stabilized zirconia particles.

The gap between the formed first ceramic structure 2 and the conduits constituting the molten glass conduit structure 1 (vertical tube 1a, horizontal tube 1b, and conduit 1c in FIG. 2) is reduced. For this purpose, the dimensional change (shrinkage) during sintering of the slurry body may be reduced. For this purpose, a slurry body containing stabilized zirconia particles having a large particle diameter may be used.
However, when a slurry body containing only stabilized zirconia particles having a large particle diameter is used, the compressive strength of the sintered body, that is, the first ceramic structure 2 is reduced because the bonding area between the particles is small.

On the other hand, when a slurry body containing stabilized zirconia particles having a small particle diameter is used, the sintered body, that is, the compressive strength of the first ceramic structure 2 is increased in order to bond so as to reinforce the joint point of the large particles. Get higher.
However, when a slurry body containing only stabilized zirconia particles having a small particle diameter is used, the dimensional change (shrinkage) during sintering of the slurry body becomes large, so that the first ceramic structure 2 after formation and the melt The gap between the conduits constituting the glass conduit structure 1 (vertical tubes 1a, horizontal tubes 1b, and conduits 1c in FIG. 2) is increased.

In the present invention, as described below, by using a slurry body in which two kinds of stabilized zirconia particles having different particle diameters are blended at a specific ratio, the first ceramic structure 2 after the formation and the molten glass are used. The first ceramic structure after forming the gap between the conduits constituting the conduit structure 1 for use (vertical pipe 1a, horizontal pipe 1b in FIG. 1 and conduit 1c in FIG. 2) less than 0.5 mm The body 2 shall have sufficient compressive strength in the temperature range at the time of distribution | circulation of a molten glass.
That is, in the present invention, the first stabilized zirconia particles having a median diameter D50 of 0.2 to 5 μm and the second stabilized zirconia particles having a median diameter D50 of 0.2 to 2 mm are secondly stabilized. Slurry blended such that the mass ratio of the first stabilized zirconia particles to the zirconia particles (the mass of the first stabilized zirconia particles / the mass of the second stabilized zirconia particles) is 0.3 to 0.6. Is used.

  In the above slurry body, the second stabilized zirconia particles having a large median diameter D50 suppress the dimensional change (shrinkage) during sintering by forming a skeleton of the sintered body, while the median diameter D50 is small. Since the first stabilized zirconia particles reinforce the bonding of large particles serving as the skeleton of the sintered body, the compressive strength of the sintered body, that is, the first ceramic structure 2 is increased.

It is important that the first stabilized zirconia particles and the second stabilized zirconia particles not only have different particle diameters but also have a median diameter D50 in the above range.
When the median diameter D50 of the first stabilized zirconia particles is less than 0.2 μm, the powder is likely to aggregate and cannot be uniformly dispersed. As a result, a portion where the bonding points of the skeleton particles of the sintered body are not strengthened remains. Therefore, the compressive strength of the sintered body, that is, the first ceramic structure 2 is lowered.
In the present invention, since two types of stabilized zirconia particles having different median diameters D50 are mixed to form a slurry, the first stabilized zirconia particles having a small median diameter D50 are ion-exchanged water, a pH adjuster, and Then, after mixing with a ball mill together with an organic binder to be added as necessary to obtain a slurry precursor, the slurry precursor and second stabilized zirconia particles having a large median diameter D50 are mixed with a planetary mixer. A slurry body is preferred.
When the median diameter D50 of the first stabilized zirconia particles is more than 5 μm, the first stabilized zirconia particles settle when the slurry precursor is produced by the above procedure, so that a good slurry precursor (zirconia particles Cannot be obtained in a uniform manner.
Even when a slurry precursor is obtained, when a slurry body produced using the slurry precursor is sintered, the joint points of the skeletal particles of the sintered body cannot be sufficiently strengthened, Since there are many voids in the bonded body, the compressive strength of the sintered body, that is, the first ceramic structure 2 is lowered.
The first stabilized zirconia particles preferably have a median diameter D50 of 0.5 to 4 μm, and more preferably 1 to 3 μm.

  The first stabilized zirconia particles preferably have an integrated sieve 90% diameter (D90) of 10 μm or less in order to maintain the uniformity of the slurry and increase the compressive strength of the sintered body. The following is more preferable.

  When the median diameter D50 of the second stabilized zirconia particles is less than 0.2 mm, the dimensional change (shrinkage) during sintering increases.

On the other hand, when the median diameter D50 of the second stabilized zirconia particles exceeds 2 mm, the slurry precursor containing the first stabilized zirconia particles and the second stabilized zirconia particles are mixed with the planetary mixer. In addition, the first stabilized zirconia particles and the second stabilized zirconia particles are not uniformly dispersed, and a slurry having a desired composition cannot be obtained.
Even when the slurry body is obtained, when the slurry body is sintered, the bonding area as the skeleton particles of the sintered body is reduced, and the sintered body, that is, the first ceramic structure 2 is obtained. The compressive strength of is low.
The second stabilized zirconia particles preferably have a median diameter D50 of 0.25 to 1.75 μm, and more preferably 0.5 to 1.5 μm.

  The second stabilized zirconia particles have a cumulative sieve 10% diameter (D10) of 0.1 mm or more to suppress dimensional change (shrinkage) during sintering and to increase the compressive strength of the sintered body. It is preferable when making it high, and it is more preferable that it is 0.2 mm or more.

  Further, in the slurry body, when the mass ratio of the first stabilized zirconia particles to the second stabilized zirconia particles is smaller than 0.3, the skeleton particles of the sintered body are obtained when the slurry body is sintered. The joint point of the coarse particles cannot be sufficiently strengthened, and the compression strength of the sintered body, that is, the first ceramic structure 2 is lowered.

  On the other hand, when the mass ratio of the first stabilized zirconia particles to the second stabilized zirconia particles is larger than 0.6 in the slurry body, the dimensional change (shrinkage) during sintering increases.

  In the slurry body, the mass ratio of the first stabilized zirconia particles to the second stabilized zirconia particles is preferably 0.35 to 0.55, and more preferably 0.4 to 0.5.

In the present invention, the gap between the conduits constituting the molten glass conduit structure 1 (vertical pipe 1a, horizontal pipe 1b in FIG. 1 and conduit 1c in FIG. 2) and the second ceramic structure 3 is filled. In order to form the first ceramic structure 2 by sintering the slurry body, the first stabilized zirconia particles and the second stabilized zirconia particles contained in the slurry body are the first-mentioned zirconia particles described above. The composition is required to be the same as that of the ceramic structure.
For this reason, the first stabilized zirconia particles and the second stabilized zirconia particles each contain 75 wt% or more of zirconium oxide in mass% with respect to the total composition, and the proportion of cubic zirconia in the zirconium oxide is 80 wt%. % Or more.

The 1st stabilization zirconia particle and the 2nd stabilization zirconia particle contain the stabilizer added in order to make zirconium oxide into cubic zirconia which is stabilized zirconia as a remainder except a zirconium oxide. Further, the remainder may contain inevitable impurities. Moreover, as long as the present invention is not affected, other components other than zirconium oxide and the stabilizer may be contained in the first stabilized zirconia particles and the second stabilized zirconia particles up to about 8 wt% in total. . Examples of such other components include Al ₂ O ₃ and MgO which are added for improving the sinterability, and these can be contained up to about 5 wt% in total.
Stabilizers include yttrium oxide, cerium oxide, magnesium oxide, calcium oxide, erbium oxide, etc., but have excellent corrosion resistance to molten glass, are easily available, and are stable even when kept at high temperatures for a long time. For this reason, yttrium oxide and cerium oxide are preferred.
When the stabilizer contains at least one selected from the group consisting of yttrium oxide and cerium oxide, the total content of both is preferably 6 wt% or more, more preferably 8 wt% or more, and 10 wt% % Or more is more preferable.
However, if the amount of stabilizer added is too large, there are problems such as difficulty in sintering and increased raw material costs. For this reason, it is preferable that the total content rate of both is 25 wt% or less, and it is more preferable that it is 20 wt% or less.

  The content of zirconium oxide in the first stabilized zirconia particles and the second stabilized zirconia particles varies depending on the amount of stabilizer added, but is 75 wt% or more in order to bring the thermal expansion coefficient into a predetermined range, and 80 wt% % Or more is preferable, and 85 wt% or more is more preferable. On the other hand, the upper limit of the content of zirconium oxide in the first stabilized zirconia particles and the second stabilized zirconia particles is about 94 wt% in consideration of the addition amount of the stabilizer.

  In the present invention, since two types of stabilized zirconia particles having different median diameters D50 are mixed to form a slurry, the first stabilized zirconia particles having a small median diameter D50 are ion-exchanged water, a pH adjuster, and Then, after mixing with a ball mill together with an organic binder to be added as necessary to obtain a slurry precursor, the slurry precursor and second stabilized zirconia particles having a large median diameter D50 are mixed with a planetary mixer. A slurry body is used.

As described above, in the present invention, since the first stabilized zirconia particles and the second stabilized zirconia particles having different median diameters D50 are mixed to form a slurry, the first stabilization with a small median diameter D50 is performed. A zirconia particle is mixed with a ball mill together with ion-exchanged water, a pH adjuster, and an organic binder to be added if necessary to obtain a slurry precursor, and then the slurry precursor and the second stable material having a large median diameter D50. Zirconia particles are preferably mixed with a planetary mixer to form a slurry.
However, the method for preparing the slurry body is not limited to this, and for example, a generally known powder or slurry mixing method can also be used.

In the above slurry body preparation method, the pH adjuster is used when the slurry precursor is produced, in order to uniformly disperse the first stabilized zirconia particles in the ion exchange water, the pH is weakly alkaline. It is because it is necessary to adjust to (pH 7-9 grade).
As the pH adjuster, CaO, ammonia, potassium carbonate and the like can be used. Among these, CaO is preferable because it is easy to handle and has little residue after heating.
When using CaO as a pH adjuster, it is preferable that it is 0.01-0.2 wt% by mass% with respect to the whole composition of a slurry body, it is more preferable that it is 0.02-0.1 wt%. More preferably, it is 03-0.5 wt%.

In order to improve the handleability at room temperature, the slurry body is mixed with an organic binder as necessary.
As the organic binder, methyl cellulose, liquid paraffin, polyethylene glycol or the like can be used. As an organic binder containing methylcellulose as a component, for example, there is a product name Metroose of Shin-Etsu Chemical Co., Ltd.
Since the organic binder burns and scatters during the sintering of the slurry, if the amount of the organic binder is too high, it remains as carbon after combustion.
For this reason, the blending amount of the organic binder is preferably 0.5 wt% or less, more preferably 0.3 wt% or less, and more preferably 0.2 wt% or less in terms of mass% with respect to the total composition of the slurry body. Is more preferable.

The blending ratio of the zirconia particles (first stabilized zirconia particles and second stabilized zirconia particles) and ion-exchanged water in the slurry body is such that the filling property of the slurry body, that is, the molten glass conduit structure 1 is determined. Fillability when filling a slurry body in the gap between the constituent conduits (vertical pipe 1a, horizontal pipe 1b in FIG. 1 and conduit 1c in FIG. 2) and the second ceramic structure 3, and normal temperature It is selected in consideration of handling in
The blending ratio of the zirconia particles (first stabilized zirconia particles and second stabilized zirconia particles) and ion-exchanged water in the slurry body is zirconia particles (first stabilized zirconia particles and second stabilized zirconia particles). It is preferable that it is 8-25 wt% in the mass% of a zirconia particle with respect to the total mass of a zirconia particle) and ion-exchange water, It is more preferable that it is 10-20 wt%, It is further more preferable that it is 12-18 wt%.

The gap between the conduit (the vertical tube 1a, the horizontal tube 1b in FIG. 1 and the conduit 1c in FIG. 2) constituting the molten glass conduit structure 1 and the second ceramic structure 3 was filled with a slurry body. Then, in order to remove the ion exchange water contained in the slurry body, it is dried in the air.
Thereafter, the slurry body is sintered at a temperature of 1200 to 1700 ° C.
When it is less than 1200 ° C., the first stabilized zirconia particles and the second stabilized zirconia particles contained in the slurry body are not sintered. If it exceeds 1700 ° C., the strength of the conduits (vertical tube 1a, horizontal tube 1b in FIG. 1 and conduit 1c in FIG. 2) made of platinum or a platinum alloy constituting the molten glass conduit structure 1 may be reduced. is there.
The sintering temperature of the slurry body is preferably 1250 to 1600 ° C, and more preferably 1300 to 1500 ° C.

  In the present invention, the gap between the conduit constituting the molten glass conduit structure 1 (vertical tube 1a, horizontal tube 1b in FIG. 1 and conduit 1c in FIG. 2) and the first ceramic structure 2 is set to 0. In order to make it less than 5 mm, it is required that the dimensional change (shrinkage) during sintering of the slurry is small. In this regard, the volume reduction rate before and after sintering is preferably 10% or less, more preferably 7% or less, and even more preferably 4% or less. That is, the volume ratio before and after sintering ((volume after heating / volume before heating) × 100) is preferably 90% or more, more preferably 93% or more, and still more preferably 96% or more.

  In the present invention, the sintered body has a sufficient compressive strength in the temperature range during the flow of the molten glass in order to suppress the deformation of the conduit constituting the molten glass conduit structure 1 by the expansion pressure applied from the molten glass. It is required to do. Specifically, the compressive strength at 1400 ° C. of the sintered body is preferably 5 MPa or more, more preferably 8 MPa or more, and further preferably 10 MPa or more.

  The glass manufacturing apparatus of the present invention uses the molten glass transport equipment element of the present invention as at least a part of the flow path of the molten glass. As an example of the glass manufacturing apparatus of this invention, the vacuum degassing apparatus using the molten glass conveyance equipment element of this invention is mentioned as at least one part of the flow path of molten glass. The glass manufacturing apparatus of the present invention is not particularly limited as long as it uses the molten glass conveying equipment element of the present invention as at least a part of the flow path of the molten glass, and the upstream glass melting tank and the downstream glass sheet A molding apparatus (for example, a float bath) may be included.

The molten glass used in the present invention is preferably the following alkali-free glass whose melting point is about 100 ° C. higher than that of soda lime glass.
In mass percentage display based on oxide,
SiO _2: 50~73%,
Al ₂ O _3: 10.5~24%,
B ₂ O _3: 0~12%,
MgO: 0 to 8%,
CaO: 0 to 14.5%,
SrO: 0 to 24%,
BaO: 0 to 13.5%,
MgO + CaO + SrO + BaO: 8-29.5%,
ZrO ₂ : 0 to 5%,
Alkali-free glass containing

When considering the solubility with a high strain point, preferably, by mass percentage display on the oxide basis,
SiO _2: 58~66%,
Al ₂ O _3: 15~22%,
B ₂ O _3: 5~12%,
MgO: 0 to 8%,
CaO: 0-9%,
SrO: 3 to 12.5%,
BaO: 0 to 2%,
MgO + CaO + SrO + BaO: 9-18%
Alkali-free glass containing

In particular, when considering solubility, preferably, by mass percentage display based on oxide,
SiO _2: 50~61.5%,
Al ₂ O _3: 10.5~18%,
B ₂ O _3: 7~10%,
MgO: 2-5%,
CaO: 0 to 14.5%,
SrO: 0 to 24%,
BaO: 0 to 13.5%,
MgO + CaO + SrO + BaO: 16-29.5%,
Alkali-free glass containing

Especially when considering the high strain point, preferably, by mass percentage display based on oxide,
SiO ₂ : 56 to 70%,
Al ₂ O _3: 14.5~22.5%,
_{B 2 O 3: 0 ~2%} ,
MgO: 0 to 6.5%
CaO: 0-9%,
SrO: 0 to 15.5%,
BaO: 0 to 2.5%,
MgO + CaO + SrO + BaO: 10 to 26%,
Alkali-free glass containing

In particular, when considering a high strain point and solubility, preferably, the oxide-based mass percentage display,
SiO _2: 54~73%,
Al ₂ O ₃ : 10.5 to 22.5%,
B ₂ O _3: 1.5~5.5%,
MgO: 0 to 6.5%
CaO: 0-9%,
SrO: 0 to 16%,
BaO: 0 to 2.5%,
MgO + CaO + SrO + BaO: 8-25%,
Alkali-free glass containing

(Experimental Examples 1-7)
As the first particles, fully stabilized zirconia particles F1, F2, and F3 having median diameters D50 of 15 μm (D90 45 μm), 0.96 μm (D90 1.8 μm), and 0.15 μm (D90 0.9 μm), respectively. Got ready. Of these particles, the particle F2 satisfies the median diameter D50 of the first stabilized zirconia particles in the present invention. All of the particles F1, F2 and F3 contained 12% by mass of yttrium oxide as a stabilizer, the zirconium oxide content was 87 wt%, and the proportion of cubic zirconia in the zirconium oxide was 95 wt%. .
Particles F1, F2 and F3: 76.85%, ion-exchanged water: 23%, CaO (pH adjuster): 0.05%, Metrose (organic binder, manufactured by Shin-Etsu Chemical Co., Ltd.): 0.1% by mass The mixture was blended in a ratio, and ball mill mixing was performed for 3 hours using a pot and balls made of zirconia to prepare a slurry precursor.
Here, in the case of using the particles F1 having a median diameter D50 of more than 5 μm, the solid content easily settled and did not become a good slurry precursor (a slurry precursor in which zirconia particles were uniformly dispersed). It was not subjected to the process.

As the second particles, fully stabilized zirconia particles C1 having median diameters D50 of 3.15 mm (D10 0.8 mm), 0.42 mm (D10 0.22 mm), and 0.08 mm (D10 0.02 mm), respectively. C2 and C3 were prepared. Of these particles, the particle C2 satisfies the median diameter D50 of the second stabilized zirconia particles in the present invention. All of the particles C1, C2 and C3 contained 12% by mass of yttrium oxide as a stabilizer, the zirconium oxide content was 87 wt%, and the proportion of cubic zirconia in the zirconium oxide was 95 wt%. .
Using a planetary mixer, the slurry precursor obtained by the above procedure and the particles C1, C2, and C3 were mixed for 20 minutes to obtain a slurry body so that the mass ratio shown in the following table was obtained.
Here, in the case of using the particles C1 having a median diameter D50 of more than 2 mm, the particles C1 and the particles F2 and F3 were not uniformly dispersed, and thus were not subjected to subsequent processes.
Five types of slurry bodies produced by the above procedure were filled in a cylindrical mold having an inner diameter of 25 mm and a height of 30 mm, dried in the air for 10 hours, and then heated using a thermostatic bath heated to 80 ° C. Let dry for hours. After drying, the mold was removed to obtain a cylindrical sample. This cylindrical sample is held in the atmosphere of 1400 ° C. for 10 hours, and after the slurry body is sintered, the volume ratio after heating is measured by cooling and measuring the external dimensions ((volume after heating / volume before heating). ) × 100) (%). Moreover, the compressive strength (MPa) in the 1400 degreeC air | atmosphere of this cylindrical sample was measured in the following procedure.

(Measurement method of compressive strength)
The compressive strength was measured by using a portal type universal testing machine (manufactured by Shimadzu Corporation: Autograph) and compressing a cylindrical sample in an oven (atmosphere) through an alumina jig. The moving speed of the crosshead was 2 mm per minute, and the maximum load was the compressive strength.
The results obtained from these measurements are summarized in the table below.

In each of Examples 1 to 7, the average open porosity was 40 to 60%, and the linear thermal expansion coefficient at 20 to 1000 ° C. was 8 × 10 ^{−6 to} 12 × 10 ⁻⁶ / ° C.
Experimental Examples 1 to 3 in which the first particle and the second particle are the particle F2 and the particle C2, respectively, and the mass ratio (first particle / second particle) of both satisfies 0.3 to 0.6. The dimensional change (shrinkage) during sintering was small, and the volume ratio after heating was 90% or more. Also, the compressive strength at 1400 ° C. was 10 MPa or more.
On the other hand, in Experimental Example 4 in which the mass ratio (first particle / second particle) of both was smaller than 0.3, the compressive strength at 1400 ° C. was as low as 2.1 MPa.
Further, in Experimental Example 5 in which the mass ratio (first particle / second particle) of both was larger than 0.6, the dimensional change (shrinkage) during sintering was large, and the volume ratio after heating was less than 90%. .
In Experimental Example 6 using the particle C3 having a median diameter D50 of less than 0.2 mm as the second particle, the dimensional change (shrinkage) during sintering was large, and the volume ratio after heating was less than 90%.
In Experimental Example 7 using the particle F3 having a median diameter D50 of less than 0.2 μm as the first particle, the compressive strength at 1400 ° C. was as low as 3.7 MPa.

(Examples and comparative examples)
In this example and comparative example, a conduit 1c shown in FIG. 2 was prepared. The conduit 1c is made of a platinum-rhodium alloy (rhodium 10% by mass), and convex portions and concave portions continuous 360 degrees in the circumferential direction are alternately provided along the axial direction, thus forming a bellows-like outer shape. . The conduit 1c has a total length of 70 mm, an outer diameter of 112 mm, and a wall thickness of 0.8 mm. The height difference between the convex portion and the concave portion is 5 mm. The distance between adjacent convex portions (or concave portions) is 14.6 mm. The length of the portion where the is formed is 58.4 mm.
Instead of the second ceramic structure 3 shown in FIG. 2, a heat-resistant cast steel ring was disposed outside the conduit 1c. The gap between the heat-resistant cast steel ring and the outermost diameter of the conduit 1c is 20 mm.
In the example, the same slurry as that prepared in Experimental Example 1 was densely filled in the gap between the heat-resistant cast steel ring and the conduit 1c. On the other hand, in the comparative example, a commercially available alumina hollow particle caster (product name: Alphalux (manufactured by Saint-Gobain Ceramics)) in the gap between the heat-resistant cast steel ring and the conduit 1c: 6. 5 × 10 ⁻⁶ / ° C., compressive strength at 1400 ° C .: 1.2 MPa). After sufficiently drying the test body prepared by the above procedure, the slurry was heated to 1300 ° C. in an electric furnace provided in the portal universal testing machine to sinter the slurry body (Example), from above. A load of 500 N was continuously applied so as to be uniform, and the resulting pressure displacement (compression strain) was continuously measured. FIG. 3 is a graph showing the measurement results, showing the relationship between the load time and the amount of compressive strain.
As is clear from FIG. 3, it is clear that the shrinkage of the conduit 1c cannot be suppressed in the comparative example using the alumina hollow particle caster having insufficient filling property and insufficient high-temperature strength (compressive strength at 1400 ° C.). . On the other hand, in the example using the slurry body of Experimental Example 1, the slurry body can be filled in the gap between the heat-resistant cast steel ring and the conduit 1c without any gap, and the dimensional change before and after heating is small, and the high temperature strength (1400 ° C. (Compressive strength) is sufficient, the shrinkage of the conduit 1c could be suppressed. FIG. 4 shows the result of observing each of the conduits 1c after performing the above-described test, and the deformation difference between them is remarkable.

Although the present invention has been described in detail and with reference to specific embodiments, it will be apparent to those skilled in the art that various modifications and variations can be made without departing from the scope and spirit of the invention.
This application is based on Japanese Patent Application No. 2011-159929 filed on July 21, 2011, the contents of which are incorporated herein by reference.

In the present invention, the first ceramic structure 2 has an average open porosity of 25 to 60%. The first ceramic structure 2 having the above composition is excellent in corrosion resistance to the molten glass, but if the average open porosity is more than 60%, the corrosion resistance to the molten glass is lowered. On the other hand, if the average open porosity is less than 25%, the thermal shock resistance of the first ceramic structure 2 is lowered. Further, since the heat capacity is increased, the conduits constituting the molten glass conduit structure 1 (vertical tube 1a, horizontal tube 1b, and conduit 1c in FIG. 2), the first ceramic structure 2, In the meantime, the thermal expansion at the time of heating or the timing of the contraction at the time of cooling tends to be shifted, and there is a possibility that cracks may occur in the conduits constituting the molten glass conduit structure 1. In addition, the time required for heating or cooling becomes longer.
The first ceramic structure 2 preferably has an average open porosity of 30 to 50%, and more preferably 35 to 45%.
Average open porosity of the first ceramic structure 2 can be determined by measurement by the Archimedes method and mercury Poroshime data.
The first ceramic structure 2 may have different open porosity depending on the part. For example, the open porosity of the portion facing the conduits (vertical tube 1a, horizontal tube 1b in FIG. 1 and conduit 1c in FIG. 2) constituting the molten glass conduit structure 1 is made lower than the other portions. Thus, the corrosion resistance against molten glass can be enhanced.

In the above slurry body, the second stabilized zirconia particles having a large median diameter D50 suppress the dimensional change (shrinkage) during sintering by forming a skeleton of the sintered body, while the median diameter D50 is small. Since the first stabilized zirconia particles reinforce the bonding points of the large particles serving as the skeleton of the sintered body, the compressive strength of the sintered body, that is, the first ceramic structure 2 is increased.

In the present invention, a slurry is formed in a gap between the conduit (the vertical tube 1a, the horizontal tube 1b, and the conduit 1c in FIG. 2) constituting the molten glass conduit structure 1 and the second ceramic structure 3. In order to form the first ceramic structure 2 by filling the body and sintering the slurry body, the first stabilized zirconia particles and the second stabilized zirconia particles contained in the slurry body are as described above. The composition is required to be the same as that of the first ceramic structure.
For this reason, the first stabilized zirconia particles and the second stabilized zirconia particles each contain 75 wt% or more of zirconium oxide in mass% with respect to the total composition, and the proportion of cubic zirconia in the zirconium oxide is 80 wt%. % Or more.

The 1st stabilization zirconia particle and the 2nd stabilization zirconia particle contain the stabilizer added in order to make zirconium oxide into cubic zirconia which is stabilized zirconia as a remainder except a zirconium oxide. Further, the remainder may contain inevitable impurities. Moreover, as long as the present invention is not affected, other components other than zirconium oxide and the stabilizer may be contained in the first stabilized zirconia particles and the second stabilized zirconia particles up to about 8 wt% in total. . Examples of such other components include Al ₂ O ₃ and MgO which are added for improving the sinterability, and these can be contained up to about 5 wt% in total.
As the stabilizer, yttrium oxide, cerium oxide, magnesium oxide, calcium oxide, Erubi U there is a beam or the like, excellent in corrosion resistance against molten glass, is easily available, a stable holding at a high temperature for a long time For some reasons, yttrium oxide and cerium oxide are preferred.
When the stabilizer contains at least one selected from the group consisting of yttrium oxide and cerium oxide, the total content of both is preferably 6 wt% or more, more preferably 8 wt% or more, and 10 wt% % Or more is more preferable.
However, if the amount of stabilizer added is too large, there are problems such as difficulty in sintering and increased raw material costs. For this reason, it is preferable that the total content rate of both is 25 wt% or less, and it is more preferable that it is 20 wt% or less.

In order to improve the handleability at room temperature, the slurry body is mixed with an organic binder as necessary.
As the organic binder, methyl cellulose, liquid paraffin, polyethylene glycol or the like can be used. The organic binder for the cellulose as a component, for example, a product name Metoro's Shin-Etsu Chemical Co., Ltd..
Since the organic binder burns and scatters during the sintering of the slurry, if the amount of the organic binder is too high, it remains as carbon after combustion.
For this reason, the blending amount of the organic binder is preferably 0.5 wt% or less, more preferably 0.3 wt% or less, and more preferably 0.2 wt% or less in terms of mass% with respect to the total composition of the slurry body. Is more preferable.

(Experimental Examples 1-7)
As the first particles, fully stabilized zirconia particles F1, F2, and F3 having median diameters D50 of 15 μm (D90 45 μm), 0.96 μm (D90 1.8 μm), and 0.15 μm (D90 0.9 μm), respectively. Got ready. Of these particles, the particle F2 satisfies the median diameter D50 of the first stabilized zirconia particles in the present invention. All of the particles F1, F2 and F3 contained 12% by mass of yttrium oxide as a stabilizer, the zirconium oxide content was 87 wt%, and the proportion of cubic zirconia in the zirconium oxide was 95 wt%. .
Particles F1, F2 and F3: 76.85% deionized water: 23% CaO (pH adjusting agent) 0.05% Metoro's (the organic binder, manufactured by Shin-Etsu Chemical Co., Ltd.): 0.1% The slurry precursor was prepared by mixing at a mass ratio and performing ball mill mixing for 3 hours using a pot and balls made of zirconia.
Here, in the case of using the particles F1 having a median diameter D50 of more than 5 μm, the solid content easily settled and did not become a good slurry precursor (a slurry precursor in which zirconia particles were uniformly dispersed). It was not subjected to the process.

Claims (12)

A molten glass conduit structure including at least one conduit made of platinum or a platinum alloy, a first ceramic structure disposed around the conduit, and a second positioned around the first ceramic structure A method for producing a molten glass conveying equipment element having a ceramic structure of
In the gap between the conduit and the second ceramic structure, zirconium oxide is contained in an amount of 75 wt% or more by mass% based on the total composition, and the proportion of cubic zirconia in the zirconium oxide is 80 wt% or more. A first stabilized zirconia having a median diameter D50 of 0.2 to 5 μm, containing 6 to 25 wt% of the total content of at least one selected from the group consisting of yttrium oxide and cerium oxide as a stabilizer Particles, and a second stabilized zirconia particle having a median diameter D50 of 0.2 to 2 mm, a mass ratio of the first stabilized zirconia particle to the second stabilized zirconia particle (first stabilized zirconia) The slurry body was mixed so that the mass of the particles / the mass of the second stabilized zirconia particles) was 0.3 to 0.6. 1200 to 1700 the first ceramic structure by causing sintering at a temperature of ℃ is formed, the manufacturing method of the molten glass conveying equipment element.   The molten glass conduit structure has at least one first conduit having a central axis in the vertical direction and two second conduits having a central axis in the horizontal direction communicating with the first conduit. The manufacturing method of the molten-glass conveyance equipment element of Claim 1.   The manufacturing method of the molten glass conveyance equipment element of Claim 1 or 2 containing the conduit | pipe which has at least one of the convex part and 360 degree recessed part which are 360 degrees continuous as the said conduit | pipe.   The manufacturing method of the molten-glass conveyance equipment element of any one of Claims 1-3 containing the conduit | pipe by which the stirrer was provided in the inside as the said conduit | pipe.   The manufacturing method of the molten glass conveyance equipment element of any one of Claims 1-4 whose platinum or platinum alloy which comprises the said conduit | pipe is the reinforced platinum by which the metal oxide was disperse | distributed to platinum or a platinum alloy.   The 90% diameter (D90) under the cumulative sieve of the first stabilized zirconia particles is 10 μm or less, and the 10% diameter (D10) under the cumulative sieve of the second stabilized zirconia particles is 0.1 mm or more. The manufacturing method of the molten-glass conveyance equipment element of any one of Claims 1-5.   The molten glass conveying equipment element according to any one of claims 1 to 5, wherein the second ceramic structure is mainly composed of at least one selected from the group consisting of alumina, magnesia, zircon, and silica. Manufacturing method. It is a molten glass conveyance equipment element manufactured by the manufacturing method of the molten glass conveyance equipment element of any one of Claims 1-7, Comprising: The average open porosity of a said 1st ceramic structure is 25-60. %, The linear thermal expansion coefficient of the first ceramic structure at 20 to 1000 ° C. is 8 × 10 ^{−6 to} 12 × 10 ⁻⁶ / ° C., and the conduit and the first ceramic structure Molten glass transport equipment element with a gap of less than 0.5 mm.   9. The linear thermal expansion coefficient at 20 to 1000 ° C. of the first ceramic structure is within ± 15% of the linear thermal expansion coefficient at 20 to 1000 ° C. of platinum or platinum alloy constituting the conduit. The molten glass conveyance equipment element of description.   The molten glass conveyance equipment element of Claim 8 or 9 whose thickness of a said 1st ceramic structure is 15-50 mm.   The molten glass conveyance equipment element of any one of Claims 8-10 whose compressive strength in 1400 degreeC of a said 1st ceramic structure is 5 Mpa or more.   The glass manufacturing apparatus containing the molten glass conveyance equipment element of any one of Claims 8-11.

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